Evolution of disposable bamboo chopsticks into uniform carbon fibers: a smart strategy to fabricate sustainable anodes for Li-ion batteries

Future development of mini consumer electronits or large electric vehicles/power grids requires Li-ion batteries (LIBs) with not only an outstanding energy-storage performance but also a minimum cost, and the foremost sustainability. Herein, we put forward a smart strategy to convert used disposable bamboo chopsticks into uniform carbon fibers for anodes of LIBs. Bamboo chopsticks waste is recycled and simply treated by a controllable hydrothermal process performed in alkaline solutions, wherein abundant natural cellulose fibers in bamboo in situ get separated and dispersed spontaneously. After carbonization, the evolved carbon fibers exhibit superior anodic performance to the bulky bamboo carbons counterpart, and competitive electrochemical behavior and cost with commercial graphite. The performance of carbon fibers can be further upgraded by growing nanostructured metal oxides (like MnO2) firmly on each fiber scaffold to form a synergetic core-shell electrode architecture. A high reversible capacity of similar to 710 mA h g(-1) is maintained without decay up to 300 cycles. Our strategy presents a scalable route to transform chopsticks waste into carbon fibers, offering a very promising way to make sustainable anodes for LIBs and economical multi-functional carbon-based hybrids available for other practical applications.